The Collaborative International Dictionary of English v.0.48:

Tipsy \Tip"sy\, a. [Compar. Tipsier; superl. Tipsiest.]
   [Akin to tipple; cf. Prov. G. tips drunkenness, betipst
   drunk, tipsy. See Tipple.]
   1. Being under the influence of strong drink; rendered weak
      or foolish by liquor, but not absolutely or completely
      drunk; fuddled; intoxicated.
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   2. Staggering, as if from intoxication; reeling.
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            Midnight shout and revelry,
            Tipsy dance and jollity.              --Milton.
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